Shearing can contribute to yaupon holly decline

September 14, 2013|Tom MacCubbin, IN THE GARDEN

Q. Our yaupon holly hedge is dying in sections. Do you have a cure?

A. Native yaupon hollies are traditionally sheared and this may be part of the problem. Neat, compact hedges are often marred by dead, brown sections, especially during the summer months. A number of fungal organisms are encouraged by the consistently moist environment among the dense branches to begin growth and cause plant decline.

Try to revive the affected hedge by first pruning the dead portions back into healthy wood. Then apply a fungicide for ornamental plants found at your local garden center. As the hedge recovers, consider training it to a natural and open shape for better air movement among the limbs. This allows drying between rains or waterings. When pruning is needed, resist cutting the stems back to the same height to also encourage more open plant growth and quicker drying that prevents fungal activity.

Q. Our 12-year-old oak tree has an infestation of caterpillars. I have been told they won't cause major damage and spraying is of little value. Is it true the tree is not in danger?

A. Caterpillars feasting in otherwise healthy oaks are not likely to cause major decline but these pests can make the trees look unattractive. There are also the droppings from the larva stage of usually a moth that can stain drives, sidewalks and vehicles. Most companies do not like to spray trees due to possible drift of the pesticide within the neighborhood.

When caterpillars are a major concern, some pest-control companies inject trees to get them under control. You can also apply a systemic insecticide to the soil under the trees following label instructions. Several brands are available at local garden centers that move through the roots and up to the leaves to control the caterpillars as they feed.

Q. I would like to purchase a persimmon tree for planting. What types are available and what variety do you recommend?

A. Persimmons come in two forms — ones with fruits that pucker your mouth until soft and fully ripe, known as astringent varieties and ones that are non-astringent and sweet even when firm. All ripen during the late summer and fall months.

The choice is yours, but many gardeners prefer the non-astringent types that can be consumed like an apple. Several of these varieties include Fuyu, Hana Fuyu and Suruga. If you would rather have some very tasty but not edible until mushy fruits try the Hachiya, Saijo and Tenenashi selections. All are very good and easy to grow in the home landscape.

Q. An old ligustrum planted by a builder has grown large and too close to the house. Can it be pruned to remove most of the green at this time of the year to reduce the height and width?

A. Healthy ligustrums can withstand a severe pruning most times of the year. The only time you might avoid is when severe cold weather is expected. Try selectively removing the portions back to a branch angle, bud or trunk to help maintain a good plant shape. Most plants are going to start new growth within weeks at this time of the year. Do keep your pruned ligustrum moist and apply a feeding when new growth is noted.

Q. I have a pineapple that is ready to be removed from the parent plant. Do I need to remove the plant or will it produce another fruit?

A. A quick removal is not necessary, but the original plant that bore the fruit is going to gradually decline. By the time you notice the leaves turning a yellow to brown color new shoots should develop to take their place.

Often the number of new shoots is excessive and gardens can remove a few to transplant and increase the fruit-producing collection. If needed to keep the planting attractive, portions of the older plant could be pruned away as they decline.

Q. I have a small area in the yard where I am thinking of using Roundup to kill the weeds that include bermudagrass and some St. Augustine. How long should I wait before resodding?

A. Usually you only have to wait until the unwanted greenery turns brown. Then you can remove the debris, till the soil and resod. Often this is only a matter of a week or two and this time of the year. The fact that you have bermudagrass complicates the procedure.

The initial herbicide treatment normally does not get all the bermudagrass runners surviving underground. So in this case it's probably best to remove the debris, till the soil and wait a week or two more for additional bermudagrass to sprout. Then make one more Roundup treatment to kill these sprouting sprigs and resod when these shoots decline.

Q. Our Hawaiian ti plants have grown tall and thin during the summer. Can I cut them back and will they bush out again?

A. Ti plants, which are dracaena relatives with large colorful leaves, add the tropical look to homes and landscapes. The leaves are often almost solid red to a blend of green, yellow and red colors depending on the variety. They can grow to more than 5 feet tall gradually losing their bottom leaves which makes them a bit lanky looking.

Feel free to take the pruners to these plants during the warmer months when they produce the best growth. If major pruning is needed, it's probably best to do it soon so the plants have enough warm weather left to form new bushes before the cold returns. The shoots removed can be rooted to increase your collection or share with friends.